Hack a Bench Power Supply and Multi-Charger From an Old PC Power Supply




for one thing i wanted a BENCH POWER SUPPLY but didn't want to pay $40 dollars at radio shack for one.
second i was sick of having so many chargers that i had to take with me everywhere i went for more than 24 hours, trips, vacations, family visits, etc. so i decided to build them both in one and while accomplishing those two ends i created a wonderful night-light as well!

\this will void your warranty and possibly harm you or your electronics - I take no responsibility for your actions or use of my information.

This charger is working great and i have used it for two months straight so far!

i used
1x PSU ( PC power supply ) watted at whatever you want
1x 3 Prong Outlet
1x 2 Prong Outlet
1x European power terminals (radioshack)
1x Dual USB Car Charger (Make sure you get one that will charge your phone and ipod - some won't!)(you could alternately use a USB hub but wire it to 5V DC instead of 12V DC
Misc hot-glue and solder
2x red LEDs

make sure you solder and hot-glue every connection for strength and to keep the connections from touching when charger is moved

the two outlets are wired to the 120V AC input with a switch in between but remember that if the charger is plugged into 220V AC then the outlets will both be 220V also!

The terminals for the bench power supply are just connected to the wires of different colors.

the USB ports are from disassembling a car charger and wiring it into the 12V DC (same voltage as a cars power system) but you could also use a USB hub like you would use with your PC but connect it into the 5V DC instead as that is what it runs on, but make sure that the charger will charge you phone or ipod whatever you plan on charging.(make sure you used a hub or chargeer and do not connect the 5V line straight to a plain USB port you have salvaged or you may harm your electronics from too much current even though it is at the right voltage.

the LEDs are connected to the grey and purple wires and ground.

one thing i thought of doing but didn't was adding a 12V DC cigarette lighter socket for car chargers - i will add it on the next one, but you might want to consider it for yours if you think you would use it!

PSU color codes (you can find these online or sometimes on the side with the specs of your PSU)

Yellow = +12V DC
Red = +5V DC
Orange = +3.3V DC
Black = -Ground DC
Blue = -5V DC
White = -12V DC
Grey = +5V DC for LED indicator only
Purple = +5V DC for LED indicator only
Brown = Power Load - Connect to Orange if present (if present it must be connected to orange for PSU to run)
Green = Power switch - MUST be shorted (connected) to Black for PSU to run! use this for a turn on switch if you desire one.

I think that is everything - if you have questions please comment but nothing negative please!



    • Warm and Fuzzy Contest

      Warm and Fuzzy Contest
    • Epilog X Contest

      Epilog X Contest
    • Paper Contest

      Paper Contest

    11 Discussions


    3 years ago

    Hey gang could someone explain to me the way to obtain odd voltages by combining a/the +side voltages with a -voltage(s)? TIA Stormy


    4 years ago on Introduction

    i think the blue wire should go with -12V DC and white wire should be with the-5V DC :)


    5 years ago on Introduction

    In order to charge an "iDevice" from any USB port, simply short out (solder together) the Data- and Data+ leads


    5 years ago on Introduction

    its fantastic how you put lot of useful things in your power supply, ant the fact that you made it recicling an old pc power supply worths a lot for me ! i just like to have photos from inside of it, showing how you made the connections between diferent points of the wires to get the voltages you need. also i like to know if you have some kind of protections for a overcurrent case . another nice feature that maybe you can add to your proyect is a line regulator circuit, that make the input voltage (from an ac oulet) smoother . good proyect, i hope you can take the photos soon

    regards from mexico


    5 years ago on Introduction

    You don't necessarily need the charger or hub. The amount of current applied to the load (whatever you are charging) is determined by the load itself. An iPhone, for instance, has a charging circuit inside that limits current to 1A. An iPad limits its charging current to 2A. The Amp rating for a given voltage on the PSU is the maximum that the PSU can supply, not a constant rating.

    Remember that Current is proportional to Voltage and inversely proportional to Reisistance, so

    I = E / R

    Since your E is a constant (regulated) 5 volts, the Resistance, or your load, will be the one that affects the amount of current.


    7 years ago on Introduction

    Great instructable, zapskate!

    I notice that in your list of PSU color codes, you have Purple = +5V DC for LED indicator only. In other instructables etc. I see purple marked as "Standby Power" providing 5V even when the PSU is down.

    Also my PSU has a pink line, which is connect to a red line in the same way as the brown is connect to an orange. None of the instructables mention a pink line.

    Anyway, thanks for the instructable.

    1 reply

    Reply 7 years ago on Introduction

    hey thanks for the great input! yes i just put the most common code occurances - there are always some different ones on other power supplies the purple is listed as standby led because that is what it powers on the computer when it is hooked up but youu could use it for powering something as well : D thanks for being courteous!


    7 years ago on Introduction

    Yeah no problem - i just figured if i found it useful then someone else will too! thank you for the great feedback!


    7 years ago on Introduction

    I too am building one of these for my voltage needs, and I didn't think of adding a usb port, that would be very handy! Thanks for sharing the idea.